The Molded Case Circuit Breaker product group is a member of the Low Voltage Distribution Equipment Section, which develops technical standards and guidelines for its products.
AB 1-2002 (Adoption of UL 489): Molded Case Circuit Breakers, Molded Case Switches, and Circuit-Breakers Enclosures. This standard is no longer for sale on the NEMA website. NEMA AB 1 is equivalent to the current edition of UL 489 AB 3-2006: Molded Case Circuit Breakers and their Application AB 4-2009: Guidelines for Inspection and Preventative Maintenance of Molded Case Circuits Breakers Used in Commercial and Industrial Applications